Search

The Painleve-Gullstrand coordinates are extended to describe the black hole in the cosmological environment: the Schwarzschild-de-Sitter black hole, which has two horizons. The extension is made using the Arnowitt-Deser-Misner formalism. In this extension, which describes the metric in the whole range of radial coordinates $0r_0$ are free falling towards the cosmological horizon. The existence of the stationary observer allows to determine the temperature of Hawking radiation, which is in agreement with R. Bousso and S.W. Hawking, Phys. Rev. D 54, 6312 (1996). It is the red-shifted modification of the conventional Hawking temperature determined by the gravity at the horizon. We also consider the Painlev\'e-Gullstrand coordinates and their extension for such configurations as Schwarzschild-de-Sitter white hole, where the sign of the shift function is everywhere positive; the black hole in the environment of the contracting de Sitter spacetime, where the sign of the shift function is everywhere negative; and the white hole in the contracting de Sitter spacetime, where the shift velocity changes sign at $r=r_0$., Comment: 6 pages, no figures

In this article we hypothesized that the arrow of time and space evolve in a discontinuous way in the form of quanta (t=ntp, s=mlp). We applied this reasoning to the light geodesics of Schwarzschild’s metric (dsmin=lp) and obtained different characteristics of the BH. Indeed, quantum light geodesics show that inside the BH a WH is formed and the mass (energy) is not directing towards the singularity r→0 but rather around the BH near the EH as a thick skin (tickness ). The total relativistic energy invariant is satisfied for the entire route of the photons. Subsequently, as mass (energy) is found directly at the EH, we applied the quantum tunnel effect in simple semi-classical analysis, and we obtained that particles like protons can leave the EH and that the energy associated with them is in the order of magnitude of Hawking’s radiation. However, the energy of the protons is not necessarily identified with that of the black body (photonic or electromagnetic). Finally, it would be interesting to see the impacts of this quantum light geodesics (dsmin=lp) on other cases like Kerr’s metric.

In the classical theory black holes can only absorb and not emit particles. However it is shown that quantum mechanical effects cause black holes to create and emit particles as if they were hot bodies with temperature\(\frac{{h\kappa }}{{2\pi k}} \approx 10^{ - 6} \left( {\frac{{M_ \odot }}{M}} \right){}^ \circ K\) where κ is the surface gravity of the black hole. This thermal emission leads to a slow decrease in the mass of the black hole and to its eventual disappearance: any primordial black hole of mass less than about 1015 g would have evaporated by now. Although these quantum effects violate the classical law that the area of the event horizon of a black hole cannot decrease, there remains a Generalized Second Law:S+1/4A never decreases whereS is the entropy of matter outside black holes andA is the sum of the surface areas of the event horizons. This shows that gravitational collapse converts the baryons and leptons in the collapsing body into entropy. It is tempting to speculate that this might be the reason why the Universe contains so much entropy per baryon.

It is shown that a traverse of a Black-and-White Hole (through a shaft in the interior of the central, spherical body) in free radial fall and rise is described by the Schwarzschild metric without any ambiguity. In other words, all Black Holes can also be White Holes. The relativity principle, according to which both the freely falling/rising observer Alice and a second observer Bob (sitting outside of the gravity field) have to measure the same temporal interval for the complete trip, is observed [(Δt)/(Δτ) = 1]. In the interior of the Schwarzschild radius, Alice's time τ is reversed. Kruskal charts do not present an obstacle to this result, since quadrant II can be used for ingoing traffic only, but not for outgoing traffic.

The conformal cyclic cosmological evolution of the universe is discussed with the principles of loop quantum gravity. The application of quantum mechanical aspects enables connecting surface between two cyclic aeons. From existing models entropy of conformal evolution is found to be modified in the light of this discussion. Infinite volume problem in conformal cyclic cosmology model is resolved with these loop quantum gravitational solutions. Various bouncing scale factors are compared. Conformal cyclic cosmological evolution does have a connection with the loop quantum cosmological scenario with this idea bridged. This work briefs the possible initial and final stages of the universe from the CCC and LQG scenario. In the connecting point between two aeons, the existence of curvature duality is also obtained and presented.

What is the concept in art? The materialism limitations of art renders art to the irreducible symbolism Kosuth put in his thesis with One and Three Chairs. The impossibilities of art and the unreachable cause of communication makes the personal public and the public personal. I approached the question with a cosmological consciousness -- a hypothesis I never dreamed of proving, yet proven from the beginning aimlessly and purposelessly. In the book, I attempt to give an overview of how I approached photography from a developmental psychology, quantum-physic-photochemistry, and conceptual art perspective, from the traditional media of film, CCD, and CMOS, to a satellite-signal-device paradigmatic method. From the scattered works of mine, I hope a precursor to astrophotography can be paved in the message from an anthropological art history perspective., {"references":["Alderman, E. & Kennedy, C. (1991). In Our Defense: The Bill of Rights in Action. Perennial. ISBN: 978-0380717200.","Apple (2019). Apple introduces dual camera iPhone 11. Apple Inc. https://www.apple.com/newsroom/2019/09/apple-introduces-dual-camera-iphone-11/","Bandura, A. (2009). Social Cognitive Theory of Mass Communication. Media Psychology, 3:3, 265-299. https://doi.org/10.1207/S1532785XMEP0303_03","Bohm, D. (2005). Wholeness and the Implicit Order. Taylor and Francis Group. ISBN: 0-203995155.","Bollas, C. (1993). The Fascist State of Mind. In Being a Character: Psychoanalysis and Self Experience, 193-217. Routledge. ISBN: 978- 0415088152.","Lodermeyer, P., de Jongh, K., and Gold, S. (2009). Personal Structures: Time, Space, Existence Number one. DuMont. ISBN: 978-3832192792.","Ehrenreich, J. T., Fairholme, C. P., Buzzella, B. A., Ellard, K. K., & Barlow, D. H. (2007). The Role of Emotion in Psychological Therapy. Clinical psychology : a publication of the Division of Clinical Psychology of the American Psychological Association, 14(4), 422–428. https://doi.org/10.1111/j.1468-2850.2007.00102.x","Hobbes, T. (1651). The Leviathan.","Huffpost (31.07.2017). The Gao Brothers' 'The Execution Of Christ' Comes To SHOWStudio After Being Forbidden In China (PHOTOS). Huffpost, Culture & Arts. https://www.huffpost.com/entry/the-gao- brothers-the-exec_n_1720743/amp","Joseph, E. D. (1987). The Consciousness of Being Conscious. Journal of the American Psychoanalytic Association, 35(1), 5–22. https://doi.org/10.1177/000306518703500101","Kaldor, M. (2011). War and Economic Crisis. In Calhoun, C. & Derluguian, G. (eds) The Deepening Crisis: Governance Challenges after Neoliberalism (New York, NY, 2011; online edn, NYU Press Scholarship Online, 24 Mar. 2016). https://doi.org/10.18574/nyu/9780814772805.003.0006","Klotz, F. G. (2020). The Military Case for Extending the New START Agreement. Santa Monica, CA: RAND Corporation. https://doi.org/10.7249/PE350","Kosuth, J. (1969). Art After Philosophy. Language and Concepts, 841-847. https://www.robertspahr.com/teaching/hnm/joseph_kosuth_art_after_philosophy.pdf","Laville, H. (2000). 'What kind of Man are you? - Masculinity in Oliver Stone's JFK. 49th Parallel, 5. https://fortyninthparalleljournal.files.wordpress.com/2014/07/1-laville- what-kind-of-man.pdf","Longarino, D. (18.10.2019). Converting the Converters: Advocates in China Make the Case for LGBT-Affirming Mental Health Care. China File. https://www.chinafile.com/reporting-opinion/viewpoint/converting-converters","Möller, F. (2016). Politics and Art. Oxford Handbook Topics in Politics (online edn, Oxford Academic, 6 Aug. 2015). https://doi.org/10.1093/oxfordhb/9780199935307.013.13","Nietzsche, F. W. (1886). Beyond Good and Evil: Prelude to a Philosophy of the Future.","Pachankis, J. E. (2007). The psychological implications of concealing a stigma: A cognitive-affective-behavioral model. Psychological Bulletin, 133(2), 328–345. https://doi.org/10.1037/0033-2909.133.2.328","Pachankis, Y. I. (2022). Cosmoconsciousness and White Hole. Internet Archive. https://archive.org/details/cosmoconsciousness","Rummel, R. J. (1981). The Just Peace*. Understanding Conflict and War, 5, Sage Publications. https://www.hawaii.edu/powerkills/TJP.CHAP2.HTM","Sarfarazi, M. P. (2022). A Deeper Look into the Origins, Types, and Treatment of Narcissism - Part XV of: Organic Life Experience and its Distortions or Reversal. Spiritual Psychology 101 Series. Academia. https://www .academia.edu/85300818/A_Deeper_Look_into_the_Origin s_Types_and_Treatment_of_Narcissism_Part_XV_of_Organic_Life_Experience_and_its_Distortion_or_Reversal","Spence, J. D. (1990). The Search for Modern China. W. W. Norton & Company. ISBN: 978-0393307801.","Tong, P. Y. (2012). An Account of Development of Performance Art in China from 1979-2010. PhD thesis, University of the Arts London. https://ualresearchonline.arts.ac.uk/id/eprint/8753/1/Tong-PhD-thesis-2015.pdf","Zeigler-Hill, V. & Marcus, D. K. (2016). The Dark Side of Personality: Science and Practice in Social, Personality, and Clinical Psychology. American Psychological Association. ISBN: 978-1433821875."]}

Multi Verse Optimization (MVO) technique is a newly developed population based algorithm established on the perception of white holes and black holes in a multi-verse for finding out all possibilit...

Last sentence of Einstein was, “Let me complete the Circle” and first sentence of our article is, “We have completed the circle”. We believed that the universe inside an atom is just like a galaxy of particles inside it and its subatomic particles, even every photon possess a galaxy of sub-photons inside it. Energy is stored in the form of energy pool in the center of each atom and sub-atomic particle. From this energy pool, particles are generating i.e. energy is converting into particles. While in some sub-atomic galaxies, particles are trapped by the energy pool i.e. particles are converting into energy. The magnification process unfolded the mysteries of atoms and galaxies. From magnified images of atoms and subatomic particles, we concluded that atom and galaxies are wrapped in folds. Also concluded that two types of matter present in the universe, luminous (e.g. stars) and non-luminous (e.g. planets, moons) matter. The center of luminous matter (galaxies) is known as white hole while the center of non-luminous matter (galaxies) is known as black hole. White holes and black holes are actually the energy pools.

We examine the accretion of matter onto a black hole in scalar--tensor--vector gravity (STVG) also known as modified gravity (MOG). The gravitational constant is $G=G_{N} (1 + \alpha)$ where $\alpha$ is a parameter taken to be constant for static black holes in the theory. The MOG black hole is spherically symmetric and characterised by two event horizons. The matter falling into the black hole obeys the polytrope equation of state and passes through two critical points before entering the outer horizon. We obtain analytical expressions for the mass accretion rate as well as for the outer critical point, critical velocity and critical sound speed. Our results complement existing strong field tests like lensing and orbital motion and could be used in conjunction to determine observational constraints on MOG., Comment: 6 pages, 1 figure, changed to match published version

Frames adapted to Kruskal and Novikov coordinate systems are used to compute the energy of the Schwarzschild black/white hole. It turns out that no regularization procedure is necessary if the right hypersurface of simultaneity is used. The importance of using a hypersurface that is consistent with the observers who “measure” the energy is discussed. The effect that the wormhole throat may have on the total energy inside this hypersurface is also discussed; the result shows that this energy becomes the famous $$Mc^2$$ only when the throat pinches off completely. The energy of the other universe is calculated. It is shown that, because of reflections at the time and the radial axes of the Kruskal and Novikov frames with respect to the Schwarzschild frame, it is not possible to obtain the energy in both universes “simultaneously.”

In this paper we systematically study a model of spherically symmetric polymer black holes recently proposed by Gambini, Olmedo, and Pullin (GOP). Within the framework of loop quantum gravity, the quantum parameters in the GOP model depend on the minimal area gap and the size of the discretization of the physical states. In this model, a spacelike transition surface takes place of the classical singularity. By means of coordinate transformations, we first extend the metric to the white hole region, and find that the geometric structure of the quantum black hole is similar to the wormhole structure, and the radius of the most quantum region is equal to the wormhole radius. In addition, we show that the energy conditions are violated not only at throat, but also at horizons and the spatial infinities. In order to show how the quantum effects affect the spacetimes, we calculate the Ricci and Kretschmann scalars at different places. It turns out that, as expected, the most quantum region is at the throat. Finally, we consider the quasinormal modes (QNMs) of massless scalar field perturbations, electromagnetic field perturbations, and axial gravitational perturbations. QNMs in the Eikonal limits are also considered. As anticipated, the spectrum of QNMs deviates from that of the classical case due to quantum effects. Interestingly, our results show that the quasinormal frequencies of the perturbations share the same qualitative tendency while setting quantum parameters with various values in this effective model, even if the potential deviations are different with different spins., 33 pages, 11 figures; Version matches the one published in PRD

With reference to our recently proposed Planck Scale White Hole Cosmology (PS-WHC) or Flat Space Cosmology (PS-FSC), we make an attempt to quantify galactic dark matter and flat rotation speeds in terms of galactic visible matter and cosmic mass. Considering recently observed dwarf galaxies having very little dark matter and assuming a time dependent reference mass unit of $M_X\cong \left(\mbox{3.0 to 4.0}\right)\times 10^{38}$ kg, we suggest an empirical relation for galactic dark matter $M_d$ via galactic visible mass $M_v$ as,$M_d \cong \frac{M_v^{3/2}}{M_X^{1/2}}$. This relation helps in fitting flat rotation speeds starting from 8 km/sec (for Segue 2) to 500 km/sec (for UGC12591). Modifying MOND's galactic flat rotation speed relation with Hubble mass $M_0\cong \left(\frac{c^3}{2GH_0}\right)$ of the universe, ratio of galactic flat rotation speed $V_G$ to speed of light $c$ can be shown to be approximately $\frac{V_G}{c} \cong 0.5 \left(\frac{M_v}{M_0}\right)^{1/4}$. Considering the sum of galactic dark matter and visible matter, ratio of galactic flat rotation speed to speed of light can be shown to be approximately $\frac{V_G}{c}\cong 0.25 \left(\frac{M_v+M_d}{M_0}\right)^{1/4}$. With further study, dark matter's nature, effect and distribution can be understood in terms of visible matter's extended gravity and extended theories of gravity can be understood with 'distance cosmic mass' rather than the empirical 'minimum acceleration'.

Quantum gravity effects in effective models of loop quantum gravity, such as loop quantum cosmology, are encoded in the choice of so-called polymerisation schemes. Physical viability of the models, such as an onset of quantum effects at curvature scales near the Planck curvature, severely restrict the possible choices. An alternative point of view on the choice of polymerisation scheme is to choose adapted variables so that the scheme is the simplest possible one, known as $\mu_0$-scheme in loop quantum cosmology. There, physically viable models with $\mu_0$-scheme polymerise the Hubble rate $b$ that is directly related to the Ricci scalar and the matter energy density on-shell. Consequently, the onset of quantum effects depends precisely on those parameters. In this letter, we construct similar variables for black to white hole transitions modelled using the description of the Schwarzschild interior as a Kantowski-Sachs cosmology. The resulting model uses the $\mu_0$-scheme and features sensible physics for a broad range of initial conditions (= choices of black and white hole masses) and favours symmetric transitions upon invoking additional qualitative arguments. The resulting Hamiltonian is very simple and at most quadratic in its arguments, allowing for a straight forward quantisation., Comment: 13 pages, 1 figure, published version, minor improvements, references added, conclusions expanded

By modifying the basic definition of cosmic red shift, considering ‘speed of light’ as an absolute cosmic expansion rate and adopting ‘Planck mass’ as the basic seed of the observed large scale universe, it is certainly possible to review and revise the basic picture of ‘standard cosmology’ and in near future, a perfect model of ‘white hole cosmology’ can be developed. In this context we have developed five assumptions. First three assumptions are based on ‘time reversed’ black holes and seem to be well connected with General theory of relativity as well as Quantum mechanics. 4th and 5th assumptions are helpful in understanding current galactic dark matter and flat rotation speeds. It may be noted that, considering our first three assumptions and considering the Planck Legacy 2018 data’s enhanced lensing amplitude in cosmic microwave background power spectra - conceptually, a closed universe having a positive curvature seems to be a best fit for the observed universe. With reference to our recent publication [26], for clarity on the subject, in this short communication, we make an attempt to review and explain our proposed assumptions at fundamental level. Our aim is to see that, professional and non-professional cosmologists must understand the basics of workable quantum cosmology.

Biological systems like cells, bacteria, chloroplasts and other micro-organisms could exchange quantum particles like electrons, photons and gravitational waves and have large distant information teleportation. This is because that their DNAs and membranes are formed from quantum particles like electrons and protons and by their motions, some currents and waves are emerged. These waves have the main role in information teleportation. There are different methods which could be used for quantum information teleportation in biological system. Some of these mechanisms are: 1. Microbes, micro-bubbles and some other biological molecules like to form some biological lines specially near the cellular gates. Also, some biological lines may be formed between two cells. These biological lines could play the role of wires which transmit information from a place to another one. For example, some signatures of this quantum information teleportation could be seen in biological lines which are emerged near the plant cell walls or gates or close to chloroplasts. Chloroplasts shoot some spinors which maybe confined within the micro-bubbles or absorb by microbes. These bubbles and microbes may join to each other and form some biological lines which may be strengthen from a plant cell to another. These biological lines could be seen near the plant cell walls or on a metal which connects two parts of a leaf. 2. Some another signatures of “quantum photon exchange or quantum information teleportation” could be seen between microbes under the objective lenses and macro-objects on the eye lenses of a light microscope. It seems that as microscope make big images from microbes for us, produce small pictures of macro-objects for microbes such as they could diagnose them and interact with them. This property could be used in controlling microbes. 3. Another way for controlling microbes is using of virtual shapes which are induced by a special light source. For example, using a multi-gonal lamp, one can induce multi-gonal shape within the micro-bubbles. Also, this special lamp could force microbes and micro-bubbles to build multi-gonal colonies on a metal-glass slide. Maybe, by using this property, one can build a light source with the shape of anti-microbial matter and induce anti-microbial property within micro-bubbles. 4. Another main way for quantum teleportation is using of gravitational holes which may be emerged by increasing concentration of microbes and heavy cells in some points. These holes absorb microbes and micro-bubbles and conduct them to the heavy cells. Usually, there are some white holes near these dark holes which as a proposal, one can assume that these white holes are another end of gravitational holes and emit photons which are entered from dark end. 5. And finally, a very main mechanism for quantum information teleportation with microbes and controlling them is using of a holography and inducing virtual microbes and biological molecules in biological systems. For example, by a combinations of two lights with different colors under a light microscope in a dark room, one may induce some non-virtual microbes in biological systems such as each microbe interacts with a virtual microbe. This is because that light waves take photos of microbes, collide with lenses of microscopes and return to the slide and form virtual microbes or biological molecules. This technique could be used in curing diseases. Although, results of our experiments show the correctness of these mechanisms and theories, however, for the moment, we propose them only as a proposal and hypothesis and hope that other scientists do similar experiments. Also, some of our experiments may be at preliminary stages; however they could be used as a hypothesis, proposal and guidance.

This work was supported in part by Grant NSF-PHY-1903799, funds of the Hearne Institute for Theoretical Physics, CCT-LSU, Pedeciba, Fondo Clemente Estable FCE_1_2019_1_155865 and Project. No. FIS 2017-86497-C2-2-P of MICINN from Spain. J.O. acknowledges the Operative Program FEDER2014-2020 and the Consejeria de Economia y Conocimiento de la Junta de Andalucia., We continue our investigation of an improved quantization scheme for spherically symmetric loop quantum gravity. We find that in the region where the black hole singularity appears in the classical theory, the quantum theory contains semi-classical states that approximate general relativity coupled to an effective anisotropic fluid. The singularity is eliminated and the space-time can be continued into a white hole space-time. This is similar to previously considered scenarios based on a loop quantum gravity quantization., Hearne Institute for Theoretical Physics, CCT-LSU, Pedeciba NSF-PHY-1903799, MICINN from Spain FIS 2017-86497-C2-2-P, Fondo Clemente Estable FCE_1_2019_1_155865

Previously, the black hole (BH) algorithm has been subjected to various fundamental enhancements. Among others, white hole operator and local search have been embedded in the BH algorithm to improve its performance significantly. This paper shows that combination of gravitational search, white hole operator, and local search also able to improve the performance of the BH algorithm significantly.

We investigate conditions for the quasi-normal modes of a Schwarzschild white hole for lower angular momentum. In determining these normal modes, we use numerical methods to solve the solution of the linearized Einstein vacuum equations in null cone coordinates. The same model is generalized to non-local fractional operator theory where the model is solved numerically thanks to a method proposed by Toufik and Atangana. In fact, approaching this kind of problem analytically seems to be an impossible task as comprehensively articulated in the literature. We show existence of quasi-normal modes of a Schwarzschild white hole for lower angular momentum l = 2 . Moreover, the non-local fractional operator appears to be a perturbator factor for the system as shown by numerical simulations that compare the types of dynamics in the system.

Tunnels cause many traffic accidents in China every year, which is related to the inappropriate driving behaviors combined with less visual comfortability when driving across tunnels. The most common phenomenon when driving across the inlet and outlet sections of a tunnel is the abruptly varying visual brightness, causing a short-term blindness for a driver, known as the “ black hole ” and “ white hole ” effects, respectively. In this paper, we propose a tunnel brightness compensation model with spatial–temporal visual-content preservation. The highlights of this paper are twofold. 1) We analyze the visual brightness variation by introducing spatio-temporal orientation energy for a stable characterization of the visual comfortability of drivers in view of the distinguishable visual content caused by a sequential brightness variation. 2) We construct a tunnel brightness compensation model that preserves the spatial–temporal visual content by visual-content matching with multiple frames. Our method can manifestly improve the brightness quality and maintain the scene content simultaneously. Extensive visual brightness compensation experiments on 60 visual clips of inlet and outlet sections of tunnels demonstrate that the proposed method generates a state-of-the-art performance.

We study hydrodynamic models of astrophysical wormholes when water waves can be amplified in the course of propagation between two critical points where wave and current speeds coincide. Such models can be realised in shallow laboratory ducts with variable width and depths. In this paper, we derive the basic set of equations for shallow water waves on the spatially variable flow in the duct of a variable cross-section and present the asymptotic analysis of solutions in the neighbourhood of the critical points. The critical points mimic either the black hole (BH) horizon if the flow transits from the subcritical to the supercritical regime, or the white hole (WH) horizon if the flow transits from the supercritical to the subcritical regime. We study then, the wave propagation in the flow with two horizons when the flow transits first the BH horizon and then the WH one. The region between the horizons mimics a wormhole in general relativity. For the sake of completeness, we also study the successive transition through WH and BH horizons. The theoretical results are illustrated by numerical calculations of wave propagation in both these arrangements. It is shown that the wave amplification after passing the active zone between the horizons takes place in BH{WH arrangements only and can occur for different relationships between the subcritical and supercritical flow velocities. The frequency dependence of the amplification factor is obtained and quantified in terms of the velocity ratio within and outside the \wormhole domain". In the next paper, we plan to present exact solutions for the specific velocity profile., Comment: 49 pages, 18 figures, 2 tables

We investigate the geometrical structure of Vaidya's spacetime in the case of a white hole with decreasing mass, stabilising to a black hole in finite or infinite time or evaporating completely. Our approach relies on a detailed analysis of the ordinary differential equation describing the incoming principal null geodesics, among which are the generators of the past horizon. We devote special attention to the case of a complete evaporation in infinite time and establish the existence of an asymptotic light-like singularity of the conformal curvature, touching both the past space-like singularity and future time-like infinity. This singularity is present independently of the decay rate of the mass. We derive an explicit formula that relates directly the strength of this null singularity to the asymptotic behaviour of the mass function., Comment: 19 pages, 4 figures

International audience; At the end of the Hawking evaporation the horizon of a black hole enters a physical region where quantum gravity cannot be neglected. The physics of this region has not been much explored. We characterize its physics and introduce a technique to study it.

Black hole (BH) meta-heuristic optimization is a nature-inspired algorithm which mimics the behavior of black holes. The Black hole algorithm framework is implemented in this work to solve dynamic optimization of some benchmark problems encountered in chemically reacting systems. We have employed two different algorithm types which include a standalone black hole algorithm and an algorithm which combines exploration–exploitation tradeoff in the algorithm. This tradeoff is enabled through the concept of white hole (WH). We have employed both piecewise linear and piecewise constant control profiles in our simulations. The algorithms proposed are simple and are easy to implement. Case studies studied show that the novel algorithms are robust and compare very well with existing algorithms.

International audience; The idea that, after their evaporation, Planck-mass black holes might tunnel into metastable white holes has recently been intensively studied. Those relics have been considered as a dark matter candidate. We show that the model is severely constrained and underline some possible detection paths. We also investigate, in a more general setting, the way the initial black hole mass spectrum would be distorted by both the bouncing effect and the Hawking evaporation.